﻿
/**
 * author: 王贵源提供
 * Date: 2015-01-20
 * 
 * 
 * */
using System;
using System.Runtime.InteropServices;

namespace COMMON.Proxy
{
    public class IEProxy
    {
        private const int INTERNET_OPTION_PROXY = 38;
        private const int INTERNET_OPEN_TYPE_PROXY = 3;
        private const int INTERNET_OPEN_TYPE_DIRECT = 1;

        private string ProxyStr;


        [DllImport("wininet.dll", SetLastError = true)]

        private static extern bool InternetSetOption(IntPtr hInternet, int dwOption, IntPtr lpBuffer, int lpdwBufferLength);

        public struct Struct_INTERNET_PROXY_INFO
        {
            public int dwAccessType;
            public IntPtr proxy;
            public IntPtr proxyBypass;
        }

        private bool InternetSetOption(string strProxy)
        {
            int bufferLength;
            IntPtr intptrStruct;
            Struct_INTERNET_PROXY_INFO struct_IPI;

            if (string.IsNullOrEmpty(strProxy) || strProxy.Trim().Length == 0)
            {
                strProxy = string.Empty;
                struct_IPI.dwAccessType = INTERNET_OPEN_TYPE_DIRECT;
            }
            else
            {
                struct_IPI.dwAccessType = INTERNET_OPEN_TYPE_PROXY;
            }
            struct_IPI.proxy = Marshal.StringToHGlobalAnsi(strProxy);
            struct_IPI.proxyBypass = Marshal.StringToHGlobalAnsi("local");
            bufferLength = Marshal.SizeOf(struct_IPI);
            intptrStruct = Marshal.AllocCoTaskMem(bufferLength);
            Marshal.StructureToPtr(struct_IPI, intptrStruct, true);
            return InternetSetOption(IntPtr.Zero, INTERNET_OPTION_PROXY, intptrStruct, bufferLength);

        }
        public IEProxy(string strProxy)
        {
            this.ProxyStr = strProxy;
        }
        //设置代理
        public bool RefreshIESettings()
        {
            return InternetSetOption(this.ProxyStr);
        }
        //取消代理
        public bool DisableIEProxy()
        {
            return InternetSetOption(string.Empty);
        }

        public void RefreshIESettings(string strProxy)
        {
            const int INTERNET_OPTION_PROXY = 38;
            const int INTERNET_OPEN_TYPE_PROXY = 3;
            const int INTERNET_OPEN_TYPE_DIRECT = 1;

            Struct_INTERNET_PROXY_INFO struct_IPI;
            // Filling in structure
            struct_IPI.dwAccessType = INTERNET_OPEN_TYPE_PROXY;
            struct_IPI.proxy = Marshal.StringToHGlobalAnsi(strProxy);
            struct_IPI.proxyBypass = Marshal.StringToHGlobalAnsi("local");

            // Allocating memory
            IntPtr intptrStruct = Marshal.AllocCoTaskMem(Marshal.SizeOf(struct_IPI));
            if (string.IsNullOrEmpty(strProxy) || strProxy.Trim().Length == 0)
            {
                strProxy = string.Empty;
                struct_IPI.dwAccessType = INTERNET_OPEN_TYPE_DIRECT;

            }
            // Converting structure to IntPtr
            Marshal.StructureToPtr(struct_IPI, intptrStruct, true);

            bool iReturn = InternetSetOption(IntPtr.Zero, INTERNET_OPTION_PROXY, intptrStruct, Marshal.SizeOf(struct_IPI));
        }

    }
}
